Variable karat gold alloys

ABSTRACT

A gold alloy that is usable for jewelry and other applications. The gold alloy is made by combining Y % gold with Z % of a master alloy, wherein Y+Z=100. The gold alloy may be made by first forming the master alloy and then mixing the gold with the master alloy. The gold alloy may also be made by mixing gold with the elements of the master alloy without first forming the master alloy. In another embodiment, the master alloy used to make a white gold (variable) karat alloy will include from about 23.33% to about 43.33% copper, from about 23.33% to about 43.33% nickel, from about 3.33% to about 23.33% zinc, and from about 10 to about 30% silver. Another embodiment of a master alloy used to make a white gold (variable) karat alloy will include from about 43.33% to about 66% copper, from about 8 to about 39.33% nickel, and from about 4.67% to about 36.67% zinc.

CROSS-REFERENCED RELATED APPLICATIONS

This application is a continuation-in-part of prior U.S. patentapplication Ser. No. 12/143,060 filed Jun. 20, 2008. This priorapplication is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Gold has a chemical symbol “Au.” Gold has been a rare and valuable metalfor centuries. It is often a symbol of wealth and has been usedextensively for jewelry, rings, necklaces, etc. Further, gold isparticularly desirable for jewelry in that it retains its beauty andcolor and does not easily tarnish or corrode. Although gold is generallyused for jewelry and wealth, its ability to resist corrosion makes thismetal useful for other applications as well (including, for example,dentistry and electronics).

As gold is desired by many people, the price of gold continues to rise.An “ounce” of gold often costs literally hundreds of dollars on the openmarket. Because of its value, many people have sought to constructalloys of gold that contain lesser and lesser amounts of gold, but stillhave the appearance and properties of pure gold. Obviously, by reducingthe amount of gold in the alloy, the cost of the material decreases (andthus can be used for less expensive jewelry, etc.). At the same time, asthe amount of gold decreases, the resulting alloy is less likely to haveall of the properties associated with gold. For example, for jewelrymade of alloys having lesser amounts of gold, it is has been found thatthese materials are more likely to tarnish and can even cause a person'sskin to discolor. Clearly, such properties are undesirable and inhibitthe jeweler's ability to sell its product.

In the jewelry industry, the amount of gold in a particular alloy isoften measured in terms of “karats.” Pure gold (i.e., 100% gold) isreferred to as 24 karat gold. Thus, the number of “karats” in the golddivided by 24 yields the percentage of gold in the alloy. For example,an alloy of gold that has 50% gold would be referred to as a 12 karatgold. 18 karat gold would be an alloy that has 75% gold, etc. Some ofthe desirable properties of gold includes its color, its “workability”(i.e., its ability to be shaped, malleability) and its flowcharacteristics.

However, as noted above, as the amount of gold in the alloy decreases(i.e., the number of karats decreases), the material is less likely tohave the properties of pure gold. Thus, jewelers are interested infinding new alloys that could be classified as 5 karat golds, 6 karatgolds, 3 karat golds, etc., but yet still have the properties/appearanceof gold and could be used as suitable jewelry pieces. For example, manyjewelers use alloys that include platinum, palladium, or other “platinumgroup metals” in their alloys to form 6 karat gold (or other low karatgold alloys). Unfortunately, these metals are often very expensive.Thus, using these metals in the gold alloy does not lower the price ofthe jewelry piece. U.S. Pat. No. 4,446,102 is another example of a lowkarat gold alloy that does not use a platinum group metal. (This patentis expressly incorporated herein by reference). However, this patentdoes not seem to be commercially successful and, if used in jewelry,will tarnish after being worn extensively by a user.

In fact, currently there does not appear to be on the market a 6 karatgold (or low karat gold) that (1) does not include an expensive platinumgroup metal and (2) does not tarnish after being worn for extendedperiods of time. Accordingly, there is a need in the industry for a newalloy of gold that may be used as a low karat alloy that is suitable formost jewelry applications. This alloy should not tarnish or discolor theskin if used as a jewelry piece. Such an alloy is taught herein.

The nomenclature that is used herein will be as follows. It is notedthat in the United States, the Federal Trade Commission (“FTC”) hasplaced regulations on a party's use of the term “karat gold” for thosealloys that are less than 10 karats (i.e., less than 41.67% gold). See16 C.F.R. Part 23. However, other countries do not have these types ofrestrictions regarding use of the word “karat.” For purposes of thisapplication, this FTC labeling requirement will not apply. References toa variable karat gold alloy or a low karat gold alloy include thosealloys which are less than 10 karats, even down to 0 karats (in whichthere is no gold present in the alloy). Such alloys, however, areclearly “precious metal alloys.” Accordingly, these alloys may also bereferred to as precious metal alloys.

BRIEF SUMMARY OF THE INVENTION

The present embodiments teach a new type of gold alloy and a method ofmaking this gold alloy. Generally, these embodiments involve the use ofa master alloy. This master alloy has the composition of 16% silver,71.771% copper, 12% zinc, and 0.229% X, wherein X being selected fromthe group consisting of silicon, germanium, or mixtures thereof. Thismaster alloy may then be mixed with an amount of gold to form a goldalloy. In other words, the gold alloy will comprise Y % gold and Z % ofa master alloy, wherein Y+Z=100.

It should be noted one of the embodiments involves pre-forming themaster alloy and then mixing a desired percentage of the master alloywith a desired percentage of gold to form the resulting gold alloy.However, other embodiments may be designed in which the gold alloy ismade by mixing gold with the elements of the master alloy without firstforming the master alloy.

In some embodiments, the gold alloy formed may be a 6 karat gold alloysuch that the percentage of gold (Y) is 25% and the percentage of themaster alloy (Z) is 75%. In this embodiment, the overall formula of thecomposition is;

25% Au;

12% Ag;

53.828% Cu;

9% Zn; and

0.172% of X, where X is silicon, germanium and/or mixtures of siliconand germanium.

In some embodiments, the gold alloy formed may be a 3 karat gold alloysuch that the percentage of gold (Y) is 12.5% and the percentage of themaster alloy (Z) is 87.5%. In this embodiment, the overall formula ofthe composition is;

12.5% Au;

14% Ag;

62.799% Cu;

10.5% Zn; and

0.201% of X, where X is silicon, germanium and/or mixtures of siliconand germanium.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In order that the manner in which the above-recited and other featuresand advantages of the invention are obtained will be readily understood,a more particular description of the invention briefly described abovewill be rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. Understanding that these drawingsdepict only typical embodiments of the invention and are not thereforeto be considered to be limiting of its scope, the invention will bedescribed and explained with additional specificity and detail throughthe use of the accompanying drawing in which:

FIG. 1 is schematic representation of an example of how the gold alloysof the present embodiments may be made.

DETAILED DESCRIPTION OF THE INVENTION

The presently preferred embodiments of the present invention will bebest understood by reference to the drawing. It will be readilyunderstood that the components of the present invention, as generallydescribed and illustrated in the FIGURE herein, could be arranged anddesigned in a wide variety of different configurations. Thus, thefollowing more detailed description of the embodiments of the presentinvention, is not intended to limit the scope of the invention, asclaimed, but is merely representative of presently preferred embodimentsof the invention.

The present embodiments relate to novel types of gold alloys, and moreparticularly, low karat gold alloys. These gold alloys do not tarnishduring extended use and wear, and will have the appearance of pure 24karat gold, yet still only have lower amounts of gold in thecomposition, such as 25% gold, 12.5% gold, etc. Even “zero karat”gold—i.e., an alloy that does not have any gold in it, may be made. Thiszero karat gold will have the appearance of karat gold and exhibitslower tarnish characteristics than other non-gold alloys, but isobviously less expensive to make given the lack of gold in thecomposition. This zero karat alloy may be referred to as a “gold-tone”alloy.

Referring now to FIG. 1, an embodiment is shown of a method 8 that maybe used to construct a gold alloy 10. The gold alloy 10 is a variablekarat gold alloy 10, meaning that the amount of karats of gold (i.e.,the percentage of the gold in the composition) may be varied. In otherwords, the method 8 may be used to make a 12 karat gold (which is 50%gold), a 6 karat gold (which is 25% gold), a 3 karat gold (which is12.5% gold), etc. depending upon the percentage of gold 12 used. Thenumber of karats in the gold alloy 10 simply depends upon the percentageof gold (which is represented by the letter “Y”) that is used.

The gold 12 is mixed with a master alloy 16 to obtain the variable karatgold alloy 10. The percentage of the master alloy 16 is represented bythe variable “Z.” Specifically Y % Au 12 will be mixed with Z % masteralloy 16 to form the variable karat gold alloy 10. Obviously, thepercentages of gold and master alloy must add up to 100% (i.e.,Y+Z=100).

The master alloy is made up of silver (whose chemical symbol is “Ag”),copper (whose chemical symbol is “Cu”), zinc (whose chemical symbol is“Zn”) and silicon (whose chemical symbol is “Si”) and/or germanium(whose chemical symbol is “Ge”). These elements are mixed in thefollowing composition:

-   -   16% silver;    -   71.771% copper;    -   12% zinc; and    -   0.229% X, wherein X being selected from the group consisting of        silicon, germanium, or mixtures thereof.

It should be noted that in the embodiment shown in FIG. 1, the silver,zinc, copper, and Si/Ge are mixed to form the master alloy, and thenonce formed, the master alloy 16 is mixed with the gold 12 to form thevariable karat gold alloy 10. Thus, in some of the presently preferredembodiments, a supply of the master alloy 16 will be “on-hand” orpre-formed and then the gold will be added thereto. However, thoseskilled in the art will appreciate that embodiments may be constructedin which the master alloy is not pre-formed. Rather, to form thevariable karat gold alloy 10, the gold, silver, copper, zinc, andsilicon/germanium are simply mixed together (using known techniques) toform the desired gold alloy 10. Either method of forming the gold alloy10 are possible and within the scope of the present embodiments.

Examples of the variable karat gold alloy 10 will now be provided.Specifically, if a 6 karat gold alloy were desired, 25% gold would bemixed with 75% of the master alloy. Once mixed and the alloy formed(using standard methods known in the industry), the resulting alloywould have the following composition:

25% Au;

12% Ag;

53.828% Cu;

9% Zn; and

0.172% of X, X is silicon, germanium and/or a mixture of silicon andgermanium.

This 6 karat gold composition does not tarnish, is wearable, will notdiscolor the wearer's finger or skin, and has the appearance of 14 karatgold. Accordingly, this composition is desirable. Further, this alloywill have the color of karat gold and will have the flow characteristicsand workable nature of karat gold. Any number of other gold alloys maybe constructed in a similar manner. For example, if a 3 karat gold isdesired, this gold may be constructed by taking 12.5% and mixing with87.5% of the master alloy composition.

Obviously, those skilled in the art will appreciate that any number ofgold alloys may be made in a similar manner (in addition to the 3 karator 6 karat gold alloys described above). Those skilled in the art wouldunderstand how to mix the elements together to get any desired goldalloy. Specifically, using these methods, a 0 karat gold alloy could beconstructed in which the Y percentage of gold is 0 and the Z percentageof the master alloy is 100. 2 karat gold alloy could be constructed inwhich the Y percentage of gold is 8.33% and the Z percentage of themaster alloy is 91.67%. Other embodiments may be designed. For example,an alloy that is less than or equal to 20 karat gold would have a Ypercentage of gold is less than or equal to about 83.33%. Furtherembodiments may be designed in which the alloy that is less than orequal to 10 karat gold, such that the Y percentage of gold is less thanor equal to about 41.67%. Yet additional embodiments may be designed inwhich the alloy is less than or equal to 6 karat gold, such that the Ypercentage of gold is less than or equal to about 25%. Any other type ofgold alloy may be constructed, as will be appreciated by those skilledin the art. Further, any of the above-recited alloys may be made byconstructing the master alloy first, or by simply mixing the elementstogether without pre-forming a master alloy.

Once the gold alloy has been formed (by mixing an amount of the masteralloy with the amount of the pure gold), a skilled artisan will be ableto determine and calculate exactly how much silver, copper, etc., is inthe resulting alloy. However, the following ratios are helpful inexplaining the present embodiments. As noted above, in the pure (100%)master alloy, there is 16% Silver. The percentage of silver in theformed gold alloy will be proportionally decreased based upon the amountof amount of gold added to the resulting compound. Using basic rules ofportions, the following mathematical relationship can be rewritten

$\begin{matrix}{\frac{16}{100} = \frac{Z_{Ag}}{A_{MA}}} & \left( {{Equation}\mspace{14mu} 1} \right)\end{matrix}$

Where Z_(Ag) represents the percentage of silver in the resulting goldalloy and A_(MA) represents the percentage of the master alloy used toform the gold alloy.

However, it is known that the percentage of the master alloy (A_(MA))plus the percentage of the gold (Y) must equal 100. Accordingly:

Y+A_(MA)=100.  (Equation 2)

Or in other words, A_(MA)=100−Y.  (Equation 3)

Substituting this relationship into Equation 1 renders the following:

$\begin{matrix}{\frac{16}{100} = \frac{Z_{Ag}}{\left( {100 - Y} \right)}} & \left( {{Equation}\mspace{14mu} 4} \right)\end{matrix}$

If Equation 4 is solved for Z_(Ag), the following is obtained:

Z_(Ag)=(1600−16*Y)/100  (Equation 5)

which represents the percentage of silver that will be in the resultinggold alloy given as a function of the percentage of gold (represented asvariable “Y”) used to form the composition.

In addition to the 16% silver in the master alloy, there is 71.771%copper, 12% zinc and 0.229% X (wherein X is Si, Ge, or mixturesthereof). Similar mathematical ratios can be derived for each of thesecomponents in the same way. Accordingly, the following equations givethe percentages of Cu, Zn, and X existing in the resulting gold alloy asa function of the percentage of gold added to form the composition:

Z_(Zn)=(1200−12*Y)/100  (Equation 6)

wherein Y represents the percentage of gold added to form thecomposition and Z_(Zn), is the percentage of zinc in the resultingalloy;

Z_(Cu)=(7177.066667−71.7706667*Y)/100  (Equation 7)

wherein Y represents the percentage of gold added to form thecomposition and Z_(Cu) is the percentage of Cu in the resulting alloy;and

Zx=(22.933333−0.2293333*Y)/100  (Equation 8)

wherein X being selected from the group consisting of silicon,germanium, or mixtures thereof, wherein Y represents the percentage ofgold added to form the composition and Z_(X) is the percentage of X inthe resulting alloy.

Those skilled in the art will appreciate that if Y is set at “25” (i.e.,25% gold) in Equations 5-8, the composition of the 6 karat gold alloynoted above will be obtained. Likewise, if Y is set at “12.5” (i.e.,12.5% gold) the composition of the 3 karat gold alloy noted above willbe obtained. Those skilled in the art will appreciate that theseequations may be used to calculate the percentages of each elementneeded based upon the percentage of gold in the final alloy. Further,the above-recited equations are but one way of calculating the amount ofeach element in the resulting alloy; other types of similar equationsand/or scaling factors are clearly possible.

Equations 5 through 8 noted above provide an easy way for a skilledartisan to determine the amount of each element to be added to theresulting alloy. Thus, the user (as noted above) may not need topre-form the master alloy before making the gold alloy. Rather, all thatis required is to mix the elements into an alloy based upon thepercentages obtained from Equations 5 through 8. Examples showing theformulas for some karat golds less than or equal to 20 karats are givenin Table 1.

TABLE 1 0 Karat Gold 2 Karat Gold 4 Karat Gold 6 Karat Gold 0% Au 8.333%Au 16.667% Au 25% Au 16% Ag; 14.667% Ag; 13.333% Ag; 12% Ag; 71.771% Cu;65.790% Cu; 59.809% Cu; 53.828% Cu; 12% Zn; and 11% Zn; and 10% Zn; and9% Zn; and 0.229% X, 0.210% X, 0.191% X, 0.172% X, wherein X wherein Xwherein X wherein X being selected being selected being selected beingselected from the group from the group from the group from the groupconsisting of consisting of consisting of consisting of silicon,silicon, silicon, silicon, germanium, or germanium, or germanium, orgermanium, or mixtures mixtures mixtures mixtures thereof. thereof.thereof. thereof. 8 Karat Gold 10 Karat Gold 12 Karat Gold 14 Karat Gold33.33% Au 41.667% Au 50% Au 58.333% Au 10.667% Ag; 9.333% Ag; 8% Ag;6.667% Ag; 47.847% Cu; 41.866% Cu; 35.885% Cu; 29.904% Cu; 8% Zn; and 7%Zn; and 6% Zn; and 5% Zn; and 0.153% X, 0.134% X, 0.115% X, 0.096% X,wherein X wherein X wherein X wherein X being selected being selectedbeing selected being selected from the group from the group from thegroup from the group consisting of consisting of consisting ofconsisting of silicon, silicon, silicon, silicon, germanium, orgermanium, or germanium, or germanium, or mixtures mixtures mixturesmixtures thereof. thereof. thereof. thereof. 16 Karat Gold 18 Karat Gold20 Karat Gold 66.667% Au 75% Au 83.333% Au 5.333% Ag; 4% Ag; 2.667% Ag;23.924% Cu; 17.943% Cu; 11.962% Cu; 4% Zn; and 3% Zn; and 2% Zn; and0.076% X, 0.057% X, 0.038% X, wherein X wherein X wherein X beingselected being selected being selected from the group from the groupfrom the group consisting of consisting of consisting of silicon,silicon, silicon, germanium, or germanium, or germanium, or mixturesmixtures mixtures thereof. thereof. thereof.

The above-recited embodiments include alloys for gold that have lessthan 4 karats. It should be noted that, in some embodiments, thesealloys having less than 4 karats (i.e., alloys having less than about16% gold), may not be as tarnish-resistant as other alloys. Rather,based upon the usage and wear, some of these embodiments with less than16% gold may tarnish when brought into contact with the skin after longperiods. Accordingly, such embodiments with less than 16% gold may notbe as preferred as other embodiments for use in rings and other jewelryapplications. Such alloys with less than 16% gold may still be suitablefor tie-tacks or other jewelry that is not generally worn in contactwith the skin. In other situations, such alloys with less than 16% goldmay still be sufficiently tarnish resistant that they may be worn on theskin.

It should also be noted that the composition of the master alloyprovided herein may be modified as follows. In fact, various ranges maybe used for each of the component elements. For example, the followingranges may be used for a 6 karat gold alloy:

from about 43 to about 63% Cu, and more preferably from about 48 toabout 58% Cu;

from about 2 to about 16% Zn, and more preferably from about 4 to about14% Zn;

from about 2 to about 22% Ag, and more preferably from about 7 to about17% Ag;

from about 0.001 to about 2% X, and more preferably from about 0.01 toabout 1.00% X,

wherein X being selected from the group consisting of silicon,germanium, or mixtures thereof. Thus, even if the composition is variedwithin the ranges specified herein, the resulting alloy will still havethe color, flow characteristics, and workability associated with gold.

It will also be appreciated that any and/or all of embodiments describedherein may include one or more grain refiners. Those skilled in the artwill appreciate that such grain refiners could be boron, magnesium,phosphorus, or other elements. Such grain refiners may be added up to1.5%, and more preferably, up to 1%, without changing the properties ofthe alloy. Accordingly, those skilled in the art would appreciate how toimplement and use these grain refiners.

It should be noted that the present application gives various examplesof the alloys described herein used in the jewelry industry or injewelry application. Those skilled in this industry will appreciate thatthere are a variety of different applications for the alloys describedherein, including dental applications, aerospace applications,metallurgy applications, electronic devices, etc. Any application orfield interested in these gold alloys could potentially use or beinterested in the present alloys. Further, another application includesusing the alloys disclosed herein as a powder coating. In theseapplications, a powder of the alloy (such as, for example), the 6 karatalloy could be laser sintered to any substrate. Once sintered, thispowder coating retains the same properties of the alloy, thus allowingthis coating to be added to a substrate.

It is also worth noting that there are a variety of different ways knownin the industry that the alloys described herein could be added or used.For example, such alloys may be used as part of plating solutions. Otherembodiments may have these alloys electrically deposited onto asubstrate. Further application may use the alloys as part of cladmaterials or layer materials (i.e., where the alloy is a foil on a brasssubstrate (such that the customer only sees the gold layer on theoutside). Materials filled with these gold alloys may also be used.Findings, wires and rods, and other accessories may be made using thesealloys. Again, the processes used (plating, making clad materials, etc.)as well as the types of materials that can be made using these alloysinvolve standard techniques known in the gold/metallurgical industry.Those skilled in the art will appreciate that all such techniques couldbe used.

The above-recited embodiments relate to “yellow gold,” but similarconcepts could be applied to white gold alloys. For example, followingwhite gold alloy could be made as follows:

Element Alloy # 1 Alloy #2 Alloy # 3 Alloy # 4 % Cu 25 41.5 42 40 % Ni25 13.5 22 21 % Zn 10 20 11 14 % Ag 15 0 0 0 % Au 25 25 25 25Each of the above recited alloys are 6 karat white gold alloys as theyhave 25% gold. These alloys could also be used with up to 1.5%, and morepreferably, up to 1.0% grain refiners, as noted above. Such white goldalloys are premium white in color and rhodium plating is unnecessary.These alloys have an 18 Karat White gold appearance. All white andyellow gold alloys are composited without platinum group elements. Grainrefiners do not significantly affect the color or tarnish resistance ofthe alloy but may have an affect on other properties.

The white gold alloys may have different compositions than that whichwas noted above. For example, the following ranges may be used for a 6karat white gold alloy:

from about 15 to about 52% Cu, and more preferably from about 20 toabout 47% Cu;

from about 3.5 to about 35% Ni, and more preferably from about 8.5 toabout 30% Ni;

from about 0 to about 30% Zn, and more preferably from about 5 to about25% Zn;

from about 5 to about 25% Ag, and more preferably from about 10 to about20% Ag;

Again, for all of these alloys within the ranges, grain refiners may beused from up to about 1.5%, and more preferably, up to about 1%. Suchwhite gold alloys are premium white in color and rhodium plating isunnecessary. These alloys have an 18 Karat White gold appearance. Allwhite and yellow gold alloys are composited without platinum groupelements.

As with the embodiments discussed above, the present embodiments ofwhite gold may also be made by constructing a master alloy and thenmixing this master alloy with a quantity of gold to create the desiredcomposition. Likewise, the gold and other elements may be mixed together(without first forming a master alloy) to create the desired alloy.

For example, a master alloy could be made with the following formulathat would be useful for making white gold:

33.333% Cu;

33.333% Ni;

13.333% Zn; and

20% Ag.

Again, this master alloy could then be mixed with various amounts ofgold to create a white gold. For example, this master alloy may be madeand then mixed with gold such that there is 25% gold and 75% of themaster alloy in the final mixture, thereby creating a 6 karat whitegold. If 50% of the master alloy is mixed with 50% gold, a 12 karatwhite gold is formed. Those skilled in the art would appreciate thatadditional types of gold alloys may be formed. Similarly, those skilledin the art would appreciate that the white gold alloy may be constructedwithout first creating the master alloy. Rather, using the techniquesdescribed herein, the exact weight percentages of the gold, copper,nickel, silver, and zinc may be mixed together to form the desired whitegold alloy.

The above recited master alloy may be modifies as follows:

-   -   The amount of copper may be from about 23.333% to about 43.333%,        and more preferably from about 28.333% to about 38.333%;    -   The amount of nickel may be from about 23.333% to about 43.333%,        and more preferably from about 28.333% to about 38.333%;    -   The amount of zinc may be from about 3.333% to about 23.333%,        and more preferably from about 8.333% to about 18.333%; and    -   The amount of silver may be from about 10% to about 30%, and        more preferably from about 15% to about 25%.        Again, one or more grain refiners, up to about 1.5% and more        preferably up to about 1.0% may be used as well.

Another master alloy for use in making white gold compositions couldhave the following composition:

55.333% Cu;

18% Ni; and

26.667% Zn.

This master alloy could then be mixed with various amounts of gold tocreate various alloys of white gold, as taught herein. This master alloycould be modified as follows:

-   -   The amount of copper may be from about 45.333% to about 65.333%,        and more preferably from about 50.333% to about 60.333%;    -   The amount of nickel may be from about 8% to about 28%, and more        preferably from about 13% to about 23%; and    -   The amount of zinc may be from about 16.667% to about 36.667%,        and more preferably from about 21.667% to about 31.667%;        One or more grain refiners, up to about 1.5% and more preferably        up to about 1.0% may be used as well.

A third master alloy for use in making white gold compositions couldhave the following composition:

56% Cu;

29.333% Ni; and

14.667% Zn.

This master alloy could then be mixed with various amounts of gold tocreate various alloys of white gold, as taught herein. This master alloycould be modified as follows:

The amount of copper may be from about 46% to about 66%, and morepreferably from about 51% to about 61%;

-   -   The amount of nickel may be from about 19.333% to about 39.333%,        and more preferably from about 24.333% to about 34.333%; and    -   The amount of zinc may be from about 4.667% to about 24.667%,        and more preferably from about 9.667% to about 19.667%;        One or more grain refiners, up to about 1.5% and more preferably        up to about 1.0% may be used as well.

A fourth master alloy for use in making white gold compositions couldhave the following composition:

53.333% Cu;

28% Ni; and

18.667% Zn.

This master alloy could then be mixed with various amounts of gold tocreate various alloys of white gold, as taught herein. This master alloycould be modified as follows:

-   -   The amount of copper may be from about 43.333% to about 63.333%,        and more preferably from about 48.333% to about 58.333%;    -   The amount of nickel may be from about 18% to about 38%, and        more preferably from about 23% to about 33%; and    -   The amount of zinc may be from about 8.667% to about 28.667%,        and more preferably from about 13.667% to about 23.667%;        One or more grain refiners, up to about 1.5% and more preferably        up to about 1.0% may be used as well.

Again, all of these master alloys described herein could be used to formwhite gold alloys with any desired gold content. Those skilled in theart will appreciate how this may be accomplished.

A more general master alloy for the white gold may be of the formula

from about 43.33% to about 66% copper;

from about 8 to about 39.33% nickel; and

from about 4.67% to about 36.67% zinc.

This formula may, of course, include one or more grain refiners and maybe used to form variable karat white gold alloys. Specifically, all ofthe master alloys for the white golds may be combined with gold, astaught herein, to form different gold alloys. For example, if thesemaster alloys are combined with 50% gold, then there will be 12 karatgold alloy formed. If these master alloys are combined with 12.5% gold,then a 3 karat gold alloy is formed.

The present invention may be embodied in other specific forms withoutdeparting from its structures, methods, or other essentialcharacteristics as broadly described herein and claimed hereinafter. Thedescribed embodiments are to be considered in all respects only asillustrative, and not restrictive. The scope of the invention is,therefore, indicated by the appended claims, rather than by theforegoing description. All changes that come within the meaning andrange of equivalency of the claims are to be embraced within theirscope.

1-10. (canceled)
 11. A master alloy for combining with gold to make avariable karat white gold alloy, the master alloy comprising: from about23.33% to about 43.33% copper; from about 23.33% to about 43.33% nickel;from about 3.33% to about 23.33% zinc; and from about 10 to about 30%silver.
 12. A master alloy for combining with gold to make a variablekarat white gold alloy as in claim 11, the master alloy comprising about33.33% copper; about 33.33% nickel; about 13.33% zinc; and about 20%silver.
 13. A master alloy for combining with gold to make a variablekarat white gold alloy as in claim 11, the master alloy comprising fromabout 28.33% to about 38.33% copper; from about 28.33% to about 38.33%nickel; from about 8.33% to about 18.33% zinc; and from about 15 toabout 25% silver. 14-25. (canceled)
 26. A master alloy as in claim 11further comprising a grain refiner in the amount of less than or equalto 1.5%. 27-30. (canceled)